This invention relates generally to the field of vests or other body-worn devices or articles of clothing which contain means to cool the wearer by removing body heat and exhausting it to the ambient air. In particular, the invention relates to such vests and devices where the body heat is removed by passing air through tubes mounted on or within the vest or device, the air absorbing the body heat prior to it being exhausted.
Many occupations require the wearing of heavy, stiff, thick or padded articles of clothing, and in particular vests which have these properties. For examples, many workers must wear vests or body suits containing multiple pockets or retainers for equipment, or workers such as policemen wear protective bullet-proof vests. While of obvious benefit to the wearer, these vests can be uncomfortable in hot weather or when the wearer performs exerting tasks, as they tend to trap the body heat produced by the wearer. In southern climates, this uncomfortable heat-trapping side effect sometimes results in a personal decision not to wear the vest, which is not desirable.
Attempts have been made to solve the heat-trapping problem by providing internal circulation systems within the vest or article of clothing. Such devices are shown for example in U.S. Pat. No. 5,255,390 to Gross et al., U.S. Pat. No. 5,050,240 to Sayre U.S. Pat. No. 5,005,216 to Blackburn et al., and U.S. Pat. No. 3,348,236 to Copeland. These devices utilize an outside source of pressurized air or fluid to pass cool air or fluid into the internal conduits, which is then exhausted or recirculated after absorbing body heat from the wearer. Siple, in U.S. Pat. No. 2,648,325, while directed at producing a body warming vest, is relevant in that it discloses a closed circulating system with no outside fluid source, where the temperature of the fluid is raised by chemical means and the circulation occurs as a function of the breathing or movement of the wearer, the expansion and contraction of the chest pressing against bulbs which force fluid flow in a single direction because of the presence of a single one-way valve in each conduit. This construction would not work for cooling the wearer, since there is not provided any means to exhaust and replace, or to cool the fluid, once it has absorbed body heat from the wearer.
It is an object of this invention to provide an article of clothing, and in particular a vest, which cools the wearer by removing body heat, where the heat is absorbed by relatively cooler air drawn from the outside ambient air which is passed through conduits in the article of clothing and exhausted, such that the system does not recirculate the air. It is a further object to provide such a device where the air is drawn into and expelled from the device with no outside pressurization means or forced air pumping apparatus, such that the device is self-ventilating. It is a further object to provide such a device where the expansion and contraction of the chest of the wearer, or physical body movement, is sufficient to cause air warmed by body heat to be exhausted from the device into the outside atmosphere and is sufficient to cause relatively cooler air to be drawn into the device from the outside atmosphere. It is a further object to provide such a device which contains multiple pairs of one-way check valves mounted in individual conduits, where the valve pairs are oriented such that flow through the conduit occurs in a single direction only, where the conduits may comprise tubes, bladders, bulbs or combinations thereof to provide the self-ventilation means to pass air through the device. These and other objects not expressly stated will be accomplished as set forth in the disclosure below.